1. Field of the Invention
This invention relates to a digital data recording and reproducing device such as a so-called digital video tape recorder for recording and reproducing digital video signals.
2. Description of the Prior Art
In the usual digital video tape recorder, digital video signals are recorded together with redundant bits for protecting digital video signals transmitted through a recording and reproducing system. In such a system, the reproduced digital video signal obtained in the reproducing system is processed for data error correction using said redundant bits. Subsequently, a check is done as to whether there is any error in the corrected data, and then an error concealment is effected, in which erroneous data that could have not been corrected by said data error correction is interpolated with adjacent correct data.
Meanwhile, in the prior art digital video tape recorder the error concealment is done by making a check as to whether there is any error in the reproduced digital video signal using the same judgement level during a reproducing operation at a different tape speed from the tape speed at the time of the recording as that during the normal reproducing operation. In a tape recorder of helical scan type utilizing a rotary head, however, large portions of the recorded signal may be skipped during the different speed reproducing operation. For this reason, when a digital video signal is dealt with, the minimum amount of data needed to be free from error for sufficient error concealment is missing the reproduced digital signal, so that considerable errors appear in the reproduction on the screen.